How to handle duplicate virtual channels with vchannel command

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TPeterson
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Joined: Thu May 31, 2007 8:29 pm

How to handle duplicate virtual channels with vchannel command

Postby TPeterson » Sat Dec 15, 2018 10:58 pm

The lineup.xml file provided from the tuner's IP address has no information about the rf channel associated with a given guide number and it appears that the IP address channel scan simply ignores duplicate VC assignments, such we have in the Bay Area for FOX (2.x) and ABC (7.x). Am I missing a key something here or is creating ones own scan file using hdhomerun_config.exe and eschewing the vchannel command the only way to allow access to such duplicates?

gtb
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Re: How to handle duplicate virtual channels with vchannel command

Postby gtb » Sun Dec 16, 2018 3:11 am

The lineup.xml file provided from the tuner's IP address has no information about the rf channel associated with a given guide number
Well, it does if you include the ?tuning value criteria [yes, these criteria/selectors are not well documented]
and it appears that the IP address channel scan simply ignores duplicate VC assignments
It does not ignore them, but it will choose the freq/program which has the "best" signal and report only that one for each major/minor. There is no way to access the "less best" channel. Of course, there are specific cases where "best" is not really "best" for your situation. There are understood solutions to influence "best", but they are not always easy or cheap to implement depending on the specifics. I suspect (I am not going to spend time on the FCC site right now) that in addition to the main transmitter frequencies changing (which will impact "best"), some of the translators (as I recall that includes at least the Fox one) are going to be changing (which will also impact "best"), so things will get different soonish (well, soonish in geologic time scales, as in early/mid 2020), so do not expect anything to stay especially stable.

If your solution needs access to tune to a specific freq/program you need to look elsewhere than the lineup.json at this time.

It should be noted that there have been hints that at some point in the future a future enhancement may be released which will allow one to chose alternative network id sources (this turns out to be especially important in the UK for freeview where it has been asked for since close to day zero). When any such capability might be available (or whether it would address your specifics) is unknown, so if you need something now, look to alternatives (likely via the libhdhomerun API).

MatthewLundberg
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Joined: Mon May 08, 2017 3:57 pm

Re: How to handle duplicate virtual channels with vchannel command

Postby MatthewLundberg » Sun Dec 16, 2018 5:01 pm

Well, it does if you include the ?tuning value criteria [yes, these criteria/selectors are not well documented]
Where did you find that, if I may ask? Are these parameters documented at all?

gtb
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Re: How to handle duplicate virtual channels with vchannel command

Postby gtb » Sun Dec 16, 2018 5:40 pm

[removed by moderator]

TPeterson
Posts: 22
Joined: Thu May 31, 2007 8:29 pm

Re: How to handle duplicate virtual channels with vchannel command

Postby TPeterson » Mon Feb 04, 2019 4:30 pm

I've found the answer to my original question. For anyone else who may have the same issue: note that the response to http://<tuner IP>/tuners.html?page=tuner<n> shows the frequency that tuner<n> is currently on so one can deduce which of the duplicate VC is in use. Then you can use the non-vchannel tuning method to invoke the other station if desired.


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